Conventionally, plastic materials derived from limited resource petroleum have been widely used; however, in the recent years, techniques with less burdens on the environment have been spotlighted. In view of the technical background, materials using cellulose fibers, which are biomass existing in nature in large amounts have been remarked.
Patent Publication 1 discloses a fine cellulose fiber composite containing fine cellulose fibers having a carboxyl group content of from 0.1 to 3 mmol/g and a surfactant adsorbed thereto. In addition, Patent Publication 2 describes cellulose nanofibers in which a linear or branched molecule is bound with a cellulose molecule via a carboxy group and an amino group.
Patent Publication 1: Japanese Patent Laid-Open No. 2011-140738
Patent Publication 2: WO 2013/077354